/* SPDX-License-Identifier: GPL-2.0-only */
/*
* arch/arm/include/asm/cacheflush.h
*
* Copyright (C) 1999-2002 Russell King
*/
#ifndef _ASMARM_CACHEFLUSH_H
#define _ASMARM_CACHEFLUSH_H
#include <linux/mm.h>
#include <asm/glue-cache.h>
#include <asm/shmparam.h>
#include <asm/cachetype.h>
#include <asm/outercache.h>
#define CACHE_COLOUR(vaddr) ((vaddr & (SHMLBA - 1)) >> PAGE_SHIFT)
/*
* This flag is used to indicate that the page pointed to by a pte is clean
* and does not require cleaning before returning it to the user.
*/
#define PG_dcache_clean PG_arch_1
/*
* MM Cache Management
* ===================
*
* The arch/arm/mm/cache-*.S and arch/arm/mm/proc-*.S files
* implement these methods.
*
* Start addresses are inclusive and end addresses are exclusive;
* start addresses should be rounded down, end addresses up.
*
* See Documentation/core-api/cachetlb.rst for more information.
* Please note that the implementation of these, and the required
* effects are cache-type (VIVT/VIPT/PIPT) specific.
*
* flush_icache_all()
*
* Unconditionally clean and invalidate the entire icache.
* Currently only needed for cache-v6.S and cache-v7.S, see
* __flush_icache_all for the generic implementation.
*
* flush_kern_all()
*
* Unconditionally clean and invalidate the entire cache.
*
* flush_kern_louis()
*
* Flush data cache levels up to the level of unification
* inner shareable and invalidate the I-cache.
* Only needed from v7 onwards, falls back to flush_cache_all()
* for all other processor versions.
*
* flush_user_all()
*
* Clean and invalidate all user space cache entries
* before a change of page tables.
*
* flush_user_range(start, end, flags)
*
* Clean and invalidate a range of cache entries in the
* specified address space before a change of page tables.
* - start - user start address (inclusive, page aligned)
* - end - user end address (exclusive, page aligned)
* - flags - vma->vm_flags field
*
* coherent_kern_range(start, end)
*
* Ensure coherency between the Icache and the Dcache in the
* region described by start, end. If you have non-snooping
* Harvard caches, you need to implement this function.
* - start - virtual start address
* - end - virtual end address
*
* coherent_user_range(start, end)
*
* Ensure coherency between the Icache and the Dcache in the
* region described by start, end. If you have non-snooping
* Harvard caches, you need to implement this function.
* - start - virtual start address
* - end - virtual end address
*
* flush_kern_dcache_area(kaddr, size)
*
* Ensure that the data held in page is written back.
* - kaddr - page address
* - size - region size
*
* DMA Cache Coherency
* ===================
*
* dma_flush_range(start, end)
*
* Clean and invalidate the specified virtual address range.
* - start - virtual start address
* - end - virtual end address
*/
struct cpu_cache_fns {
void (*flush_icache_all)(void);
void (*flush_kern_all)(void);
void (*flush_kern_louis)(void);
void (*flush_user_all)(void);
void (*flush_user_range)(unsigned long, unsigned long, unsigned int);
void (*coherent_kern_range)(unsigned long, unsigned long);
int (*coherent_user_range)(unsigned long, unsigned long);
void (*flush_kern_dcache_area)(void *, size_t);
void (*dma_map_area)(const void *, size_t, int);
void (*dma_unmap_area)(const void *, size_t, int);
void (*dma_flush_range)(const void *, const void *);
} __no_randomize_layout;
/*
* Select the calling method
*/
#ifdef MULTI_CACHE
extern struct cpu_cache_fns cpu_cache;
#define __cpuc_flush_icache_all cpu_cache.flush_icache_all
#define __cpuc_flush_kern_all cpu_cache.flush_kern_all
#define __cpuc_flush_kern_louis cpu_cache.flush_kern_louis
#define __cpuc_flush_user_all cpu_cache.flush_user_all
#define __cpuc_flush_user_range cpu_cache.flush_user_range
#define __cpuc_coherent_kern_range cpu_cache.coherent_kern_range
#define __cpuc_coherent_user_range cpu_cache.coherent_user_range
#define __cpuc_flush_dcache_area cpu_cache.flush_kern_dcache_area
/*
* These are private to the dma-mapping API. Do not use directly.
* Their sole purpose is to ensure that data held in the cache
* is visible to DMA, or data written by DMA to system memory is
* visible to the CPU.
*/
#define dmac_flush_range cpu_cache.dma_flush_range
#else
extern void __cpuc_flush_icache_all(void);
extern void __cpuc_flush_kern_all(void);
extern void __cpuc_flush_kern_louis(void);
extern void __cpuc_flush_user_all(void);
extern void __cpuc_flush_user_range(unsigned long, unsigned long, unsigned int);
extern void __cpuc_coherent_kern_range(unsigned long, unsigned long);
extern int __cpuc_coherent_user_range(unsigned long, unsigned long);
extern void __cpuc_flush_dcache_area(void *, size_t);
/*
* These are private to the dma-mapping API. Do not use directly.
* Their sole purpose is to ensure that data held in the cache
* is visible to DMA, or data written by DMA to system memory is
* visible to the CPU.
*/
extern void dmac_flush_range(const void *, const void *);
#endif
/*
* Copy user data from/to a page which is mapped into a different
* processes address space. Really, we want to allow our "user
* space" model to handle this.
*/
extern void copy_to_user_page(struct vm_area_struct *, struct page *,
unsigned long, void *, const void *, unsigned long);
#define copy_from_user_page(vma, page, vaddr, dst, src, len) \
do { \
memcpy(dst, src, len); \
} while (0)
/*
* Convert calls to our calling convention.
*/
/* Invalidate I-cache */
#define __flush_icache_all_generic() \
asm("mcr p15, 0, %0, c7, c5, 0" \
: : "r" (0));
/* Invalidate I-cache inner shareable */
#define __flush_icache_all_v7_smp() \
asm("mcr p15, 0, %0, c7, c1, 0" \
: : "r" (0));
/*
* Optimized __flush_icache_all for the common cases. Note that UP ARMv7
* will fall through to use __flush_icache_all_generic.
*/
#if (defined(CONFIG_CPU_V7) && \
(defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V6K))) || \
defined(CONFIG_SMP_ON_UP)
#define __flush_icache_preferred __cpuc_flush_icache_all
#elif __LINUX_ARM_ARCH__ >= 7 && defined(CONFIG_SMP)
#define __flush_icache_preferred __flush_icache_all_v7_smp
#elif __LINUX_ARM_ARCH__ == 6 && defined(CONFIG_ARM_ERRATA_411920)
#define __flush_icache_preferred __cpuc_flush_icache_all
#else
#define __flush_icache_preferred __flush_icache_all_generic
#endif
static inline void __flush_icache_all(void)
{
__flush_icache_preferred();
dsb(ishst);
}
/*
* Flush caches up to Level of Unification Inner Shareable
*/
#define flush_cache_louis() __cpuc_flush_kern_louis()
#define flush_cache_all() __cpuc_flush_kern_all()
static inline void vivt_flush_cache_mm(struct mm_struct *mm)
{
if (cpumask_test_cpu(smp_processor_id(), mm_cpumask(mm)))
__cpuc_flush_user_all();
}
static inline void
vivt_flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end)
{
struct mm_struct *mm = vma->vm_mm;
if (!mm || cpumask_test_cpu(smp_processor_id(), mm_cpumask(mm)))
__cpuc_flush_user_range(start & PAGE_MASK, PAGE_ALIGN(end),
vma->vm_flags);
}
static inline void vivt_flush_cache_pages(struct vm_area_struct *vma,
unsigned long user_addr, unsigned long pfn, unsigned int nr)
{
struct mm_struct *mm = vma->vm_mm;
if (!mm || cpumask_test_cpu(smp_processor_id(), mm_cpumask(mm))) {
unsigned long addr = user_addr & PAGE_MASK;
__cpuc_flush_user_range(addr, addr + nr * PAGE_SIZE,
vma->vm_flags);
}
}
#ifndef CONFIG_CPU_CACHE_VIPT
#define flush_cache_mm(mm) \
vivt_flush_cache_mm(mm)
#define flush_cache_range(vma,start,end) \
vivt_flush_cache_range(vma,start,end)
#define flush_cache_pages(vma, addr, pfn, nr) \
vivt_flush_cache_pages(vma, addr, pfn, nr)
#else
void flush_cache_mm(struct mm_struct *mm);
void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end);
void flush_cache_pages(struct vm_area_struct *vma, unsigned long user_addr,
unsigned long pfn, unsigned int nr);
#endif
#define flush_cache_dup_mm(mm) flush_cache_mm(mm)
#define flush_cache_page(vma, addr, pfn) flush_cache_pages(vma, addr, pfn, 1)
/*
* flush_icache_user_range is used when we want to ensure that the
* Harvard caches are synchronised for the user space address range.
* This is used for the ARM private sys_cacheflush system call.
*/
#define flush_icache_user_range(s,e) __cpuc_coherent_user_range(s,e)
/*
* Perform necessary cache operations to ensure that data previously
* stored within this range of addresses can be executed by the CPU.
*/
#define flush_icache_range(s,e) __cpuc_coherent_kern_range(s,e)
/*
* Perform necessary cache operations to ensure that the TLB will
* see data written in the specified area.
*/
#define clean_dcache_area(start,size) cpu_dcache_clean_area(start, size)
/*
* flush_dcache_page is used when the kernel has written to the page
* cache page at virtual address page->virtual.
*
* If this page isn't mapped (ie, page_mapping == NULL), or it might
* have userspace mappings, then we _must_ always clean + invalidate
* the dcache entries associated with the kernel mapping.
*
* Otherwise we can defer the operation, and clean the cache when we are
* about to change to user space. This is the same method as used on SPARC64.
* See update_mmu_cache for the user space part.
*/
#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
void flush_dcache_page(struct page *);
void flush_dcache_folio(struct folio *folio);
#define flush_dcache_folio flush_dcache_folio
#define ARCH_IMPLEMENTS_FLUSH_KERNEL_VMAP_RANGE 1
static inline void flush_kernel_vmap_range(void *addr, int size)
{
if ((cache_is_vivt() || cache_is_vipt_aliasing()))
__cpuc_flush_dcache_area(addr, (size_t)size);
}
static inline void invalidate_kernel_vmap_range(void *addr, int size)
{
if ((cache_is_vivt() || cache_is_vipt_aliasing()))
__cpuc_flush_dcache_area(addr, (size_t)size);
}
#define ARCH_HAS_FLUSH_ANON_PAGE
static inline void flush_anon_page(struct vm_area_struct *vma,
struct page *page, unsigned long vmaddr)
{
extern void __flush_anon_page(struct vm_area_struct *vma,
struct page *, unsigned long);
if (PageAnon(page))
__flush_anon_page(vma, page, vmaddr);
}
#define flush_dcache_mmap_lock(mapping) xa_lock_irq(&mapping->i_pages)
#define flush_dcache_mmap_unlock(mapping) xa_unlock_irq(&mapping->i_pages)
/*
* flush_cache_vmap() is used when creating mappings (eg, via vmap,
* vmalloc, ioremap etc) in kernel space for pages. On non-VIPT
* caches, since the direct-mappings of these pages may contain cached
* data, we need to do a full cache flush to ensure that writebacks
* don't corrupt data placed into these pages via the new mappings.
*/
static inline void flush_cache_vmap(unsigned long start, unsigned long end)
{
if (!cache_is_vipt_nonaliasing())
flush_cache_all();
else
/*
* set_pte_at() called from vmap_pte_range() does not
* have a DSB after cleaning the cache line.
*/
dsb(ishst);
}
static inline void flush_cache_vunmap(unsigned long start, unsigned long end)
{
if (!cache_is_vipt_nonaliasing())
flush_cache_all();
}
/*
* Memory synchronization helpers for mixed cached vs non cached accesses.
*
* Some synchronization algorithms have to set states in memory with the
* cache enabled or disabled depending on the code path. It is crucial
* to always ensure proper cache maintenance to update main memory right
* away in that case.
*
* Any cached write must be followed by a cache clean operation.
* Any cached read must be preceded by a cache invalidate operation.
* Yet, in the read case, a cache flush i.e. atomic clean+invalidate
* operation is needed to avoid discarding possible concurrent writes to the
* accessed memory.
*
* Also, in order to prevent a cached writer from interfering with an
* adjacent non-cached writer, each state variable must be located to
* a separate cache line.
*/
/*
* This needs to be >= the max cache writeback size of all
* supported platforms included in the current kernel configuration.
* This is used to align state variables to their own cache lines.
*/
#define __CACHE_WRITEBACK_ORDER 6 /* guessed from existing platforms */
#define __CACHE_WRITEBACK_GRANULE (1 << __CACHE_WRITEBACK_ORDER)
/*
* There is no __cpuc_clean_dcache_area but we use it anyway for
* code intent clarity, and alias it to __cpuc_flush_dcache_area.
*/
#define __cpuc_clean_dcache_area __cpuc_flush_dcache_area
/*
* Ensure preceding writes to *p by this CPU are visible to
* subsequent reads by other CPUs:
*/
static inline void __sync_cache_range_w(volatile void *p, size_t size)
{
char *_p = (char *)p;
__cpuc_clean_dcache_area(_p, size);
outer_clean_range(__pa(_p), __pa(_p + size));
}
/*
* Ensure preceding writes to *p by other CPUs are visible to
* subsequent reads by this CPU. We must be careful not to
* discard data simultaneously written by another CPU, hence the
* usage of flush rather than invalidate operations.
*/
static inline void __sync_cache_range_r(volatile void *p, size_t size)
{
char *_p = (char *)p;
#ifdef CONFIG_OUTER_CACHE
if (outer_cache.flush_range) {
/*
* Ensure dirty data migrated from other CPUs into our cache
* are cleaned out safely before the outer cache is cleaned:
*/
__cpuc_clean_dcache_area(_p, size);
/* Clean and invalidate stale data for *p from outer ... */
outer_flush_range(__pa(_p), __pa(_p + size));
}
#endif
/* ... and inner cache: */
__cpuc_flush_dcache_area(_p, size);
}
#define sync_cache_w(ptr) __sync_cache_range_w(ptr, sizeof *(ptr))
#define sync_cache_r(ptr) __sync_cache_range_r(ptr, sizeof *(ptr))
/*
* Disabling cache access for one CPU in an ARMv7 SMP system is tricky.
* To do so we must:
*
* - Clear the SCTLR.C bit to prevent further cache allocations
* - Flush the desired level of cache
* - Clear the ACTLR "SMP" bit to disable local coherency
*
* ... and so without any intervening memory access in between those steps,
* not even to the stack.
*
* WARNING -- After this has been called:
*
* - No ldrex/strex (and similar) instructions must be used.
* - The CPU is obviously no longer coherent with the other CPUs.
* - This is unlikely to work as expected if Linux is running non-secure.
*
* Note:
*
* - This is known to apply to several ARMv7 processor implementations,
* however some exceptions may exist. Caveat emptor.
*
* - The clobber list is dictated by the call to v7_flush_dcache_*.
*/
#define v7_exit_coherency_flush(level) \
asm volatile( \
".arch armv7-a \n\t" \
"mrc p15, 0, r0, c1, c0, 0 @ get SCTLR \n\t" \
"bic r0, r0, #"__stringify(CR_C)" \n\t" \
"mcr p15, 0, r0, c1, c0, 0 @ set SCTLR \n\t" \
"isb \n\t" \
"bl v7_flush_dcache_"__stringify(level)" \n\t" \
"mrc p15, 0, r0, c1, c0, 1 @ get ACTLR \n\t" \
"bic r0, r0, #(1 << 6) @ disable local coherency \n\t" \
"mcr p15, 0, r0, c1, c0, 1 @ set ACTLR \n\t" \
"isb \n\t" \
"dsb" \
: : : "r0","r1","r2","r3","r4","r5","r6", \
"r9","r10","ip","lr","memory" )
void flush_uprobe_xol_access(struct page *page, unsigned long uaddr,
void *kaddr, unsigned long len);
#ifdef CONFIG_CPU_ICACHE_MISMATCH_WORKAROUND
void check_cpu_icache_size(int cpuid);
#else
static inline void check_cpu_icache_size(int cpuid) { }
#endif
#endif